This invention relates to a bipolar tonsillar probe for tonsil reduction with radio frequency energy in an electrosurgical procedure.
Our prior U.S. Pat. No. 6,387,093, whose contents are hereby incorporated by reference, describes a novel electrode and electrosurgical procedure for treating Obstructive Sleep Apnea Syndrome (OSAS) by Radio Frequency Thermal Ablation (RFTA), which uses radio frequency (RF) heating to create targeted tissue ablation resulting in tissue volume reduction of tongue base tissue. This procedure uses a unipolar electrode.
Children having tonsillar problems, such as enlarged tonsils, are conventionally treated by removal of the tonsils. However, it-has been suggested recently that such a procedure (tonsillectomy usually accompanied by adenoidectomy) can be replaced with a procedure which involves no surgery, produces minimal post-procedure pain, and shortens the recovery period. This new procedure involves temperature-controlled RF submucosal tissue volume reduction, using relatively low frequency electrosurgery (in the low KHz range) and also a unipolar electrode with the conventional ground plate.
It has been our experience that low frequency electrosurgery inherently tends to produce high temperatures in the tissues treated; thus the need for the temperature-controller. Moreover, the need for the temperature-controller leads to a more complex structure of the electrosurgical electrode.
The present invention describes a novel RF tonsillar probe that can be used with low power electrosurgical apparatus for the purpose of implementing RFTA with a relatively simple, easily learned procedure.
Briefly stated, the novel probe comprises a generally elongated insulated structure having at a proximal end a cable connector for coupling to the bipolar outlet of electrosurgical apparatus, two internal insulated wires leading from the cable to a distal end that is angled downwardly and that terminates in two laterally-spaced needle electrodes whose tips are exposed. Our novel probe works best with relatively high-frequency RF electrosurgical currents in excess of 1.5 MHz, preferably in the range of 1.5-4 MHz. We have found that the combination of the bipolar mode with electrosurgical currents in the MHz range causes relatively low tissue temperatures avoiding the need for the addition of a complicated temperature-controller structure and suitable circuitry, and the bipolar action confines the RFTA effect to the tissue region between the two active needle electrodes. The downwardly-extending distal end housing the two needle electrodes also simplifies for the surgeon placement of the needle electrodes at the tonsil site where the volumetric shrinkage is desired. The downward angle preferably is about 60xc2x0-90xc2x0, preferably about 75xc2x0. Preferably, the needle portions adjacent the distal end are covered with a thin electrically-insulating coating to prevent electrosurgical currents from entering the tonsil tissue except from the needle tips.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described the preferred embodiments of the invention.